proginn-lib/dist/hash/crc32.js

var poly = 0xEDB88320; // reverse polynomial
// build table
function signed_crc_table() {
    var c, n, k, table = new Array(256);
    for (n = 0; n < 256; n++) {
        c = n;
        for (k = 0; k < 8; k++) {
            if (c & 1) {
                c = poly ^ (c >>> 1);
            }
            else {
                c = c >>> 1;
            }
        }
        table[n] = c >>> 0;
    }
    return typeof Int32Array !== 'undefined' ? new Int32Array(table) : table;
}
var T = signed_crc_table();
function crc32_str(str, seed = 0) {
    var C = seed ^ -1;
    for (var i = 0, L = str.length, c, d; i < L;) {
        c = str.charCodeAt(i++);
        if (c < 0x80) {
            C = (C >>> 8) ^ T[(C ^ c) & 0xFF];
        }
        else if (c < 0x800) {
            C = (C >>> 8) ^ T[(C ^ (192 | ((c >> 6) & 31))) & 0xFF];
            C = (C >>> 8) ^ T[(C ^ (128 | (c & 63))) & 0xFF];
        }
        else if (c >= 0xD800 && c < 0xE000) {
            c = (c & 1023) + 64;
            d = str.charCodeAt(i++) & 1023;
            C = (C >>> 8) ^ T[(C ^ (240 | ((c >> 8) & 7))) & 0xFF];
            C = (C >>> 8) ^ T[(C ^ (128 | ((c >> 2) & 63))) & 0xFF];
            C = (C >>> 8) ^ T[(C ^ (128 | ((d >> 6) & 15) | ((c & 3) << 4))) & 0xFF];
            C = (C >>> 8) ^ T[(C ^ (128 | (d & 63))) & 0xFF];
        }
        else {
            C = (C >>> 8) ^ T[(C ^ (224 | ((c >> 12) & 15))) & 0xFF];
            C = (C >>> 8) ^ T[(C ^ (128 | ((c >> 6) & 63))) & 0xFF];
            C = (C >>> 8) ^ T[(C ^ (128 | (c & 63))) & 0xFF];
        }
    }
    return C ^ -1;
}
function decimalToHex(num) {
    var str = (num >>> 0).toString(16);
    var padLen = 8 - str.length;
    return padLen > 0 ? new Array(padLen + 1).join('0') + str : str;
}
function crc32(str) {
    return decimalToHex(crc32_str(str));
}
export default crc32;